ALEXANDRIA, Va. (WJLA) - Police are investigating after a school resource officer accidentally fired his gun at a Northern Virginia middle school on Tuesday morning.

Alexandria Police say the officer was in his office at George Washington Middle School when the gun discharged.

"I have some serious concerns and some serious questions that I'd like answered," said parent Andi Snow. "Here we have a highly trained five year veteran of the police force and somehow, we don't know how his service weapon was discharged?"

Authorities say the officer checked immediately to see if anyone was injured. No one was hurt and the officer reported the incident to school staff and his supervisor.

On Tuesday night, Alexandria Police Chief Michael Brown told ABC7 News the bullet actually went through a wall inside the school. He would not say whether that was the wall of a classroom because the investigation into what happened is still underway.

Brown showed up at a George Washington Middle School PTA meeting along with the school superintendent, to answer questions from parents.

"I can honestly say from the facts I have right now, it appears to be an accidental event," he told the crowd. "But I also want to tell you, any use of a weapon by an officer in this department is taken with a great deal of severity and reviewed with a great deal of scrutiny."

Brown said that he would be transparent about the case and planned to release the results of the investigation once it has been reviewed by the Commonwealth's Attorney's Office.

"We are very thankful no one was hurt, and we will get back with the district and students and parents with the findings, once they are complete," said Brown.

"I wanted to hear those questions directly. I wanted to know what people were saying and to hear the answers, even though I've had at least two lengthy conversations with the chief today," said the mayor. "The safety of our children is paramount for all of us."

Classes at the school continued on schedule after it was determined that no one had been hurt.

The school resource officer is a five-year veteran of the Alexandria Police force. He's been put on administrative leave as police investigate the incident, which is standard procedure.